Sealing member for prosthetic heart valve

ABSTRACT

An implantable prosthetic valve can include a radially expandable and collapsible annular frame having an inflow end and an outflow end. A leaflet structure can be positioned within the frame. An annular inner skirt can be positioned around an inner surface of the frame, wherein the inner skirt includes an outflow edge portion secured to the frame and an inflow edge portion that wraps around the inflow end of the frame and extends at least partially along an outer surface of the frame, with the inflow edge portion being secured to the frame. An outer skirt can be positioned around the outer surface of the frame, wherein the outer skirt comprises an outflow edge portion secured to the frame and an inwardly folded inflow edge portion that is secured to the inflow edge portion of the inner skirt.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application Ser.No. 62/546,915, filed Aug. 17, 2017, which is incorporated by referenceherein.

FIELD

The present disclosure relates to implantable, expandable prostheticdevices and to methods and apparatuses for such prosthetic devices.

BACKGROUND

The human heart can suffer from various valvular diseases. Thesevalvular diseases can result in significant malfunctioning of the heartand ultimately require replacement of the native valve with anartificial valve. There are a number of known artificial valves and anumber of known methods of implanting these artificial valves in humans.Because of the drawbacks associated with conventional open-heartsurgery, percutaneous and minimally-invasive surgical approaches aregarnering intense attention. In one technique, a prosthetic valve isconfigured to be implanted in a much less invasive procedure by way ofcatheterization. For example, collapsible transcatheter prosthetic heartvalves can be crimped to a compressed state and percutaneouslyintroduced in the compressed state on a catheter and expanded to afunctional size at the desired position by balloon inflation or byutilization of a self-expanding frame or stent.

A prosthetic valve for use in such a procedure can include a radiallycollapsible and expandable frame to which leaflets of the prostheticvalve can be coupled. For example, U.S. Pat. Nos. 6,730,118, 7,393,360,7,510,575, and 7,993,394, which are incorporated herein by reference,describe exemplary collapsible and expandable transcatheter prostheticheart valves.

A prosthetic valve for use in such a procedure can include a radiallycollapsible and expandable frame to which leaflets of the prostheticvalve can be coupled, and which can be percutaneously introduced in acollapsed configuration on a catheter and expanded in the desiredposition by balloon inflation or by utilization of a self-expandingframe or stent. A challenge in catheter-implanted prosthetic valves iscontrol of perivalvular leakage around the valve, which can occur for aperiod of time following initial implantation. An additional challengeincludes the process of crimping such a prosthetic valve to a profilesuitable for percutaneous delivery to a subject.

SUMMARY

Embodiments of a radially collapsible and expandable prosthetic valveare disclosed herein that include an improved outer skirt for reducingperivalvular leakage, as well as related methods and apparatusesincluding such prosthetic valves. In several embodiments, the disclosedprosthetic valves are configured as replacement heart valves forimplantation into a subject.

In one representative embodiment, an implantable prosthetic heart valvecan comprise an annular frame comprising an inflow end and an outflowend and being radially collapsible and expandable between a radiallycollapsed configuration and a radially expanded configuration, and aleaflet structure positioned within the frame and secured thereto. Theprosthetic heart valve can further comprise an annular inner skirtpositioned around an inner surface of the frame, wherein the inner skirtcomprises an outflow edge portion secured to the frame and an inflowedge portion secured to the frame. In some embodiments, the inflow edgeportion wraps around the inflow end of the frame and extends at leastpartially along an outer surface of the frame. The prosthetic heartvalve can also have an outer skirt positioned around the outer surfaceof the frame, wherein the outer skirt comprises an outflow edge portionsecured to the frame and an inwardly folded inflow edge portion that issecured to the inflow edge portion of the inner skirt.

In some embodiments, the inflow edge portion of the inner skirt can besecured to the frame at discrete, spaced-apart locations. In suchembodiments, the inflow edge portion of the outer skirt can be securedto the inflow edge portion of the inner skirt only at locations on theinflow edge portion of the inner skirt that are secured to the frame.

In some embodiments, the frame can further comprise a plurality ofstruts forming a plurality of circumferentially spaced apices at theinflow end of the frame, and the inflow edge portion of the inner skirtcan be secured to the frame only at the apices.

In some embodiments, the inflow edge portion of the outer skirt can besecured to the inflow edge portion of the inner skirt only at locationson the inflow edge portion of the inner skirt that are secured to theapices of the frame. In some embodiments, the inflow edge portion of theinner skirt can be secured to the frame with discrete, spaced-apartsutures.

In some embodiments, the outflow edge portion of the outer skirt cancomprise a plurality of alternating projections and notches, and theprojections can be secured to the frame and the notches can be notdirectly secured to the frame.

In some embodiments, the outer skirt can further comprise anintermediate portion between the inflow edge portion and the outflowedge portion and the intermediate portion can comprise a plurality ofopenings. In such embodiments, the openings can be aligned with the projections.

In some embodiments, the inflow edge portion of the outer skirt cancomprise a plurality of overlapping portions that are angularly alignedwith the openings, wherein the overlapping portions are folded inwardlytowards the outflow end of the frame, and wherein the overlappingportions are secured to the inflow edge portion of the inner skirt. Insuch embodiments, the overlapping portions can be secured to the inflowedge portion of the inner skirt only at locations on the inflow edgeportion of the inner skirt that are secured to the frame. In suchembodiments, the overlapping portions can be folded such that each ofthe overlapping portions is radially aligned with a corresponding one ofthe openings when the overlapping portions are secured to the innerskirt.

In some embodiments, the outer skirt can be secured to the inner skirtby sutures. In some embodiments, the inner and outer skirts can beconfigured such that when the prosthetic valve is implanted, antegradeblood can flow through a space between the inflow edge portion of theinner skirt and the inflow edge portion of the outer skirt. In someembodiments, the inflow edge portion of the inner skirt can be looselystitched to the inflow edge portion of the outer skirt.

In another representative embodiment, an assembly for implanting aprosthetic heart valve in a patient's body is provided. The assembly cancomprise a delivery apparatus comprising an elongate shaft, and aprosthetic heart valve mounted on the shaft in a radially collapsedconfiguration for delivery into the body.

In another representative embodiment, a method of implanting aprosthetic heart valve in a patient's body is provided. The method cancomprise radially compressing the prosthetic heart valve to a radiallycompressed configuration, coupling the prosthetic heart valve to thedistal end of a delivery apparatus, inserting the distal end portion ofthe delivery apparatus and the prosthetic heart valve into a patient'sbody, positioning the prosthetic heart valve adjacent a native valve ofthe patient's heart, and radially expanding the prosthetic heart valveso that it engages the native valve. The prosthetic heart valve cancomprise an annular frame comprising an inflow end and an outflow endand being radially collapsible and expandable between a radiallycollapsed configuration and a radially expanded configuration, a leafletstructure positioned within the frame and secured thereto, an annularinner skirt positioned around an inner surface of the frame, wherein theinner skirt comprises an outflow edge portion secured to the frame andan inflow edge portion that wraps around the inflow end of the frame andextends at least partially along an outer surface of the frame, theinflow edge portion being secured to the frame, and an outer skirtpositioned around the outer surface of the frame, wherein the outerskirt comprises an outflow edge portion secured to the frame and aninwardly folded inflow edge portion that is secured to the inflow edgeportion of the inner skirt.

In some embodiments, the outer skirt can engage the native valve andantegrade blood can flow through the space between the inflow edgeportion of the outer skirt and the inflow edge portion of an inner skirtand enter space between the frame and the outer skirt to help seal theouter skirt against the native valve.

In some embodiments, the inflow edge portion of the inner skirt can besecured to the frame at discrete, space-apart locations. In suchembodiments, the inflow edge portion of the outer skirt can be securedto the inflow edge portion of the inner skirt only at locations on theinflow edge portion of the inner skirt that are secured to the frame.

The foregoing and other objects, features, and advantages of theinvention will become more apparent from the following detaileddescription, which proceeds with reference to the accompanying figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1-3 show an exemplary embodiment of a prosthetic heart valve.

FIGS. 4-10 show an exemplary frame of the prosthetic heart valve of FIG.1.

FIGS. 11-12 show an exemplary inner skirt of the prosthetic heart valveof FIG. 1.

FIG. 13 shows the prosthetic heart valve of FIG. 1 in a collapsedconfiguration and mounted on an exemplary balloon catheter.

FIGS. 14-16 show the assembly of the inner skirt of FIG. 11 with theframe of FIG. 4.

FIGS. 17-18 show the assembly of an exemplary leaflet structure.

FIG. 19 shows the assembly of commissure portions of the leafletstructure with window frame portions of the frame.

FIGS. 20-21 show the assembly of the leaflet structure with the innerskirt along a lower edge of the leaflets.

FIG. 22 shows a flattened view of an exemplary outer skirt.

FIG. 23 shows another exemplary embodiment of an outer skirt.

FIGS. 24-26 show various views of another exemplary embodiment of anouter skirt.

FIG. 27 shows a schematic view of a portion of the frame and the outerskirt of the prosthetic valve of FIG. 1 with the frame in an expandedconfiguration.

FIG. 28 shows a schematic view of the frame and the outer skirt of FIG.27 with the frame in a collapsed configuration.

FIG. 29 shows another exemplary embodiment of an outer skirt.

FIGS. 30-31 show cross-sectional views of an exemplary embodiment of aprosthetic heart valve.

FIGS. 32-34 show various views of another exemplary embodiment of anouter skirt.

FIG. 35 shows an exemplary prosthetic heart valve implanted in thenative aortic valve of a patient.

FIG. 36 shows an exemplary prosthetic heart valve and docking deviceimplanted in the pulmonary artery of a patient.

FIG. 37 shows an exemplary prosthetic heart valve and docking deviceimplanted in the native mitral valve of a patient.

FIGS. 38-39 show an alternative embodiment of a docking device for aprosthetic valve.

FIG. 40 shows an exemplary prosthetic heart valve and the docking deviceof FIGS. 38-39 implanted in the inferior vena cava of a patient.

DETAILED DESCRIPTION

FIGS. 1-3 show various views of a prosthetic heart valve 10, accordingto one embodiment. The illustrated prosthetic valve is adapted to beimplanted in the native aortic annulus, although in other embodiments itcan be adapted to be implanted in the other native annuluses of theheart (e.g., the pulmonary, mitral, and tricuspid valves). Theprosthetic valve can also be adapted to be implanted in other tubularorgans or passageways in the body. The prosthetic valve 10 can have fourmain components: a stent or frame 12, a valvular structure 14, an innerskirt 16, and a perivalvular sealing means or sealing member. Theprosthetic valve 10 can have an inflow end portion 15, an intermediateportion 17, and an outflow end portion 19. In the illustratedembodiment, the perivalvular sealing means comprises an outer skirt 18.

The valvular structure 14 can comprise three leaflets 41, collectivelyforming a leaflet structure, which can be arranged to collapse in atricuspid arrangement, as best shown in FIG. 2. The lower edge ofleaflet structure 14 desirably has an undulating, curved scalloped shape(suture line 154 shown in FIG. 21 tracks the scalloped shape of theleaflet structure). By forming the leaflets with this scallopedgeometry, stresses on the leaflets are reduced, which in turn improvesdurability of the prosthetic valve. Moreover, by virtue of the scallopedshape, folds and ripples at the belly of each leaflet (the centralregion of each leaflet), which can cause early calcification in thoseareas, can be eliminated or at least minimized. The scalloped geometryalso reduces the amount of tissue material used to form leafletstructure, thereby allowing a smaller, more even crimped profile at theinflow end of the prosthetic valve. The leaflets 41 can be formed ofpericardial tissue (e.g., bovine pericardial tissue), biocompatiblesynthetic materials, or various other suitable natural or syntheticmaterials as known in the art and described in U.S. Pat. No. 6,730,118,which is incorporated by reference in its entirety herein.

The bare frame 12 is shown in FIG. 4. The frame 12 can be formed with aplurality of circumferentially spaced slots, or commissure windows, 20(three in the illustrated embodiment) that are adapted to connect thecommissures of the valvular structure 14 to the frame, as described ingreater detail below. The frame 12 can be made of any of varioussuitable plastically-expandable materials (e.g., stainless steel, etc.)or self-expanding materials (e.g., nickel titanium alloy (NiTi), such asnitinol). When constructed of a plastically-expandable material, theframe 12 (and thus the prosthetic valve 10) can be crimped to a radiallycollapsed configuration on a delivery catheter and then expanded insidea patient by an inflatable balloon or equivalent expansion mechanism.When constructed of a self-expandable material, the frame 12 (and thusthe prosthetic valve 10) can be crimped to a radially collapsedconfiguration and restrained in the collapsed configuration by insertioninto a sheath or equivalent mechanism of a delivery catheter. Onceinside the body, the prosthetic valve can be advanced from the deliverysheath, which allows the prosthetic valve to expand to its functionalsize.

Suitable plastically-expandable materials that can be used to form theframe 12 include, without limitation, stainless steel, a biocompatible,high-strength alloys (e.g., a cobalt-chromium or anickel-cobalt-chromium alloys), polymers, or combinations thereof. Inparticular embodiments, frame 12 is made of anickel-cobalt-chromium-molybdenum alloy, such as MP35N® alloy (SPSTechnologies, Jenkintown, Pa.), which is equivalent to UNS R30035 alloy(covered by ASTM F562-02). MP35N® alloy/UNS R30035 alloy comprises 35%nickel, 35% cobalt, 20% chromium, and 10% molybdenum, by weight. WhenMP35N® alloy is used as the frame material, as compared to stainlesssteel, less material is needed to achieve the same or better performancein radial and crush force resistance, fatigue resistances, and corrosionresistance. Moreover, since less material is required, the crimpedprofile of the frame can be reduced, thereby providing a lower profileprosthetic valve assembly for percutaneous delivery to the treatmentlocation in the body.

Referring to FIGS. 4 and 5, the frame 12 in the illustrated embodimentcomprises a first, lower row I of angled struts 22 arranged end-to-endand extending circumferentially at the inflow end of the frame; a secondrow II of circumferentially extending, angled struts 24; a third row IIIof circumferentially extending, angled struts 26; a fourth row IV ofcircumferentially extending, angled struts 28; and a fifth row V ofcircumferentially extending, angled struts 32 at the outflow end of theframe. A plurality of substantially straight axially extending struts 34can be used to interconnect the struts 22 of the first row I with thestruts 24 of the second row II. The fifth row V of angled struts 32 areconnected to the fourth row IV of angled struts 28 by a plurality ofaxially extending window frame portions 30 (which define the commissurewindows 20) and a plurality of axially extending struts 31. Each axialstrut 31 and each frame portion 30 extends from a location defined bythe convergence of the lower ends of two angled struts 32 to anotherlocation defined by the convergence of the upper ends of two angledstruts 28. FIGS. 6, 7, 8, 9, and 10 are enlarged views of the portionsof the frame 12 identified by letters A, B, C, D, and E, respectively,in FIG. 5.

Each commissure window frame portion 30 connects to a respectivecommissure of the leaflet structure 14. As can be seen each frameportion 30 is secured at its upper and lower ends to the adjacent rowsof struts to provide a robust configuration that enhances fatigueresistance under cyclic loading of the prosthetic valve compared tocantilevered struts for supporting the commissures of the leafletstructure. This configuration enables a reduction in the frame wallthickness to achieve a smaller crimped diameter of the prosthetic valve.In particular embodiments, the thickness T of the frame 12 (FIG. 4)measured between the inner diameter and outer diameter is about 0.48 mmor less.

The struts and frame portions of the frame collectively define aplurality of open cells of the frame. At the inflow end of the frame 12,struts 22, struts 24, and struts 34 define a lower row of cells definingopenings 36. The second, third, and fourth rows of struts 24, 26, and 28define two intermediate rows of cells defining openings 38. The fourthand fifth rows of struts 28 and 32, along with frame portions 30 andstruts 31, define an upper row of cells defining openings 40. Theopenings 40 are relatively large and are sized to allow portions of theleaflet structure 14 to protrude, or bulge, into and/or through theopenings 40 when the frame 12 is crimped in order to minimize thecrimping profile.

As best shown in FIG. 7, the lower end of the strut 31 is connected totwo struts 28 at a node or junction 44, and the upper end of the strut31 is connected to two struts 32 at a node or junction 46. The strut 31can have a thickness 51 that is less than the thicknesses S2 of thejunctions 44, 46. The junctions 44, 46, along with junctions 64, preventfull closure of openings 40. FIG. 13 shows the prosthetic valve 10crimped on a balloon catheter. As can be seen, the geometry of thestruts 31, and junctions 44, 46, and 64 assists in creating enough spacein openings 40 in the collapsed configuration to allow portions of theprosthetic leaflets to protrude or bulge outwardly through openings.This allows the prosthetic valve to be crimped to a relatively smallerdiameter than if all of the leaflet material were constrained within thecrimped frame.

The frame 12 is configured to reduce, to prevent, or to minimizepossible over-expansion of the prosthetic valve at a predeterminedballoon pressure, especially at the outflow end portion of the frame,which supports the leaflet structure 14. In one aspect, the frame isconfigured to have relatively larger angles 42 a, 42 b, 42 c, 42 d, 42 ebetween struts, as shown in FIG. 5. The larger the angle, the greaterthe force required to open (expand) the frame. As such, the anglesbetween the struts of the frame can be selected to limit radialexpansion of the frame at a given opening pressure (e.g., inflationpressure of the balloon). In particular embodiments, these angles are atleast 110 degrees or greater when the frame is expanded to itsfunctional size, and even more particularly these angles are up to about120 degrees when the frame is expanded to its functional size.

In addition, the inflow and outflow ends of a frame generally tend toover-expand more so than the middle portion of the frame due to the“dog-boning” effect of the balloon used to expand the prosthetic valve.To protect against over-expansion of the leaflet structure 14, theleaflet structure desirably is secured to the frame 12 below the upperrow of struts 32, as best shown in FIG. 1. Thus, in the event that theoutflow end of the frame is over-expanded, the leaflet structure ispositioned at a level below where over-expansion is likely to occur,thereby protecting the leaflet structure from over-expansion.

In one type of prosthetic valve construction, portions of the leafletsprotrude longitudinally beyond the outflow end of the frame when theprosthetic valve is crimped if the leaflets are connected too close tothe distal end of the frame. If the delivery catheter on which thecrimped prosthetic valve is mounted includes a pushing mechanism or stopmember that pushes against or abuts the outflow end of the prostheticvalve (for example, to maintain the position of the crimped prostheticvalve on the delivery catheter), the pushing member or stop member candamage the portions of the exposed leaflets that extend beyond theoutflow end of the frame. Another benefit of connecting the leaflets ata location spaced away from the outflow end of the frame is that whenthe prosthetic valve is crimped on a delivery catheter, the outflow endof the frame 12 rather than the leaflets 41 is the proximal-mostcomponent of the prosthetic valve 10. As such, if the delivery catheterincludes a pushing mechanism or stop member that pushes against or abutsthe outflow end of the prosthetic valve, the pushing mechanism or stopmember contacts the outflow end of the frame, and not leaflets 41, so asto avoid damage to the leaflets.

Also, as can be seen in FIG. 5, the openings 36 of the lowermost row ofopenings in the frame are relatively larger than the openings 38 of thetwo intermediate rows of openings. This allows the frame, when crimped,to assume an overall tapered shape that tapers from a maximum diameterat the outflow end of the prosthetic valve to a minimum diameter at theinflow end of the prosthetic valve. When crimped, the frame 12 can havea reduced diameter region extending along a portion of the frameadjacent the inflow end of the frame that generally corresponds to theregion of the frame covered by the outer skirt 18. In some embodiments,the reduced diameter region is reduced compared to the diameter of theupper portion of the frame (which is not covered by the outer skirt)such that the outer skirt 18 does not increase the overall crimp profileof the prosthetic valve. When the prosthetic valve is deployed, theframe can expand to the generally cylindrical shape shown in FIG. 4. Inone example, the frame of a 26-mm prosthetic valve, when crimped, had afirst diameter of 14 French at the outflow end of the prosthetic valveand a second diameter of 12 French at the inflow end of the prostheticvalve.

The main functions of the inner skirt 16 are to assist in securing thevalvular structure 14 to the frame 12 and to assist in forming a goodseal between the prosthetic valve and the native annulus by blocking theflow of blood through the open cells of the frame 12 below the loweredge of the leaflets. The inner skirt 16 desirably comprises a tough,tear resistant material such as polyethylene terephthalate (PET),although various other synthetic materials or natural materials (e.g.,pericardial tissue) can be used. The thickness of the skirt desirably isless than about 0.15 mm (about 6 mil), and desirably less than about 0.1mm (about 4 mil), and even more desirably about 0.05 mm (about 2 mil).In particular embodiments, the skirt 16 can have a variable thickness,for example, the skirt can be thicker at least one of its edges than atits center. In one implementation, the skirt 16 can comprise a PET skirthaving a thickness of about 0.07 mm at its edges and about 0.06 mm atits center. The thinner skirt can provide for better crimpingperformances while still providing good sealing.

The skirt 16 can be secured to the inside of frame 12 via sutures 70, asshown in FIG. 21. Valvular structure 14 can be attached to the skirt viaone or more reinforcing strips 72 (which collectively can form asleeve), for example thin, PET reinforcing strips, discussed below,which enables a secure suturing and protects the pericardial tissue ofthe leaflet structure from tears. Valvular structure 14 can besandwiched between skirt 16 and the thin PET strips 72 as shown in FIG.20. Sutures 154, which secure the PET strip and the leaflet structure 14to skirt 16, can be any suitable suture, such as Ethibond Excel® PETsuture (Johnson & Johnson, New Brunswick, N.J.). Sutures 154 desirablytrack the curvature of the bottom edge of leaflet structure 14, asdescribed in more detail below.

Some fabric skirts comprise a weave of warp and weft fibers that extendperpendicularly to each other and with one set of the fibers extendinglongitudinally between the upper and lower edges of the skirt. When themetal frame to which such a fabric skirt is secured is radiallycompressed, the overall axial length of the frame increases. However, afabric skirt with limited elasticity cannot elongate along with theframe and therefore tends to deform the struts of the frame and toprevent uniform crimping.

Referring to FIG. 12, in one embodiment, the skirt 16 desirably is wovenfrom a first set of fibers, or yarns or strands, 78 and a second set offibers, or yarns or strands, 80, both of which are non-perpendicular tothe upper edge 82 and the lower edge 84 of the skirt. In particularembodiments, the first set of fibers 78 and the second set of fibers 80extend at angles of about 45 degrees (e.g., 15-75 degrees or 30-60degrees) relative to the upper and lower edges 82, 84. For example, theskirt 16 can be formed by weaving the fibers at 45 degree anglesrelative to the upper and lower edges of the fabric. Alternatively, theskirt 16 can be diagonally cut (cut on a bias) from a vertically wovenfabric (where the fibers extend perpendicularly to the edges of thematerial) such that the fibers extend at 45 degree angles relative tothe cut upper and lower edges of the skirt. As further shown in FIG. 12,the opposing short edges 86, 88 of the skirt desirably arenon-perpendicular to the upper and lower edges 82, 84. For example, theshort edges 86, 88 desirably extend at angles of about 45 degreesrelative to the upper and lower edges and therefore are aligned with thefirst set of fibers 78. Therefore the overall general shape of the skirtis that of a rhomboid or parallelogram.

FIGS. 14 and 15 show the inner skirt 16 after opposing short edgeportions 90, 92 have been sewn together to form the annular shape of theskirt. As shown, the edge portion 90 can be placed in an overlappingrelationship relative to the opposite edge portion 92, and the two edgeportions can be sewn together with a diagonally extending suture line 94that is parallel to short edges 86, 88. The upper edge portion of theinner skirt 16 can be formed with a plurality of projections 96 thatdefine an undulating shape that generally follows the shape or contourof the fourth row of struts 28 immediately adjacent the lower ends ofaxial struts 31. In this manner, as best shown in FIG. 16, the upperedge of the inner skirt 16 can be tightly secured to struts 28 withsutures 70. The inner skirt 16 can also be formed with slits 98 tofacilitate attachment of the skirt to the frame. Slits 98 can bedimensioned so as to allow an upper edge portion of the inner skirt 16to be partially wrapped around struts 28 and to reduce stresses in theskirt during the attachment procedure. For example, in the illustratedembodiment, the inner skirt 16 is placed on the inside of frame 12 andan upper edge portion of the skirt is wrapped around the upper surfacesof struts 28 and secured in place with sutures 70. Wrapping the upperedge portion of the inner skirt 16 around struts 28 in this mannerprovides for a stronger and more durable attachment of the skirt to theframe. The inner skirt 16 can also be secured to the first, second,and/or third rows of struts 22, 24, and 26, respectively, with sutures70.

Referring again to FIG. 12, due to the angled orientation of the fibersrelative to the upper and lower edges in this embodiment, the skirt canundergo greater elongation in the axial direction (i.e., in a directionfrom the upper edge 82 to the lower edge 84).

Thus, when the metal frame 12 is crimped (as shown in FIG. 13), theinner skirt 16 can elongate in the axial direction along with the frameand therefore provide a more uniform and predictable crimping profile.Each cell of the metal frame in the illustrated embodiment includes atleast four angled struts that rotate towards the axial direction oncrimping (e.g., the angled struts become more aligned with the length ofthe frame). The angled struts of each cell function as a mechanism forrotating the fibers of the skirt in the same direction of the struts,allowing the skirt to elongate along the length of the struts. Thisallows for greater elongation of the skirt and avoids undesirabledeformation of the struts when the prosthetic valve is crimped.

In addition, the spacing between the woven fibers or yarns can beincreased to facilitate elongation of the skirt in the axial direction.For example, for a PET inner skirt 16 formed from 20-denier yarn, theyarn density can be about 15% to about 30% lower than in a typical PETskirt. In some examples, the yarn spacing of the inner skirt 16 can befrom about 60 yarns per cm (about 155 yarns per inch) to about 70 yarnsper cm (about 180 yarns per inch), such as about 63 yarns per cm (about160 yarns per inch), whereas in a typical PET skirt the yarn spacing canbe from about 85 yarns per cm (about 217 yarns per inch) to about 97yarns per cm (about 247 yarns per inch). The oblique edges 86, 88promote a uniform and even distribution of the fabric material alonginner circumference of the frame during crimping so as to facilitateuniform crimping to the smallest possible diameter. Additionally,cutting diagonal sutures in a vertical manner may leave loose fringesalong the cut edges. The oblique edges 86, 88 help minimize this fromoccurring.

In alternative embodiments, the skirt can be formed from woven elasticfibers that can stretch in the axial direction during crimping of theprosthetic valve. The warp and weft fibers can run perpendicularly andparallel to the upper and lower edges of the skirt, or alternatively,they can extend at angles between 0 and 90 degrees relative to the upperand lower edges of the skirt, as described above.

The inner skirt 16 can be sutured to the frame 12 at locations away fromthe suture line 154 so that the skirt can be more pliable in that area.This configuration can avoid stress concentrations at the suture line154, which attaches the lower edges of the leaflets to the inner skirt16.

As noted above, the leaflet structure 14 in the illustrated embodimentincludes three flexible leaflets 41 (although a greater or a smallernumber of leaflets can be used). Additional information regarding theleaflets, as well as additional information regarding skirt material,can be found, for example, in U.S. patent application Ser. No.14/704,861, filed May 5, 2015, which is incorporated by reference in itsentirety.

The leaflets 41 can be secured to one another at their adjacent sides toform commissures 122 of the leaflet structure. A plurality of flexibleconnectors 124 (one of which is shown in FIG. 17) can be used tointerconnect pairs of adjacent sides of the leaflets and to connect theleaflets to the commissure window frame portions 30 (FIG. 5).

FIG. 17 shows the adjacent sides of two leaflets 41 interconnected by aflexible connector 124. Three leaflets 41 can be secured to each otherside-to-side using three flexible connectors 124, as shown in FIG. 18.Additional information regarding connecting the leaflets to each other,as well as connecting the leaflets to the frame, can be found, forexample, in U.S.

Patent Application Publication No. 2012/0123529, which is incorporatedby reference herein in its entirety.

As noted above, the inner skirt 16 can be used to assist in suturing theleaflet structure 14 to the frame. The inner skirt 16 can have anundulating temporary marking suture to guide the attachment of the loweredges of each leaflet 41. The inner skirt 16 itself can be sutured tothe struts of the frame 12 using sutures 70, as noted above, beforesecuring the leaflet structure 14 to the skirt 16. The struts thatintersect the marking suture desirably are not attached to the innerskirt 16. This allows the inner skirt 16 to be more pliable in the areasnot secured to the frame and minimizes stress concentrations along thesuture line that secures the lower edges of the leaflets to the skirt.As noted above, when the skirt is secured to the frame, the fibers 78,80 of the skirt (see FIG. 12) generally align with the angled struts ofthe frame to promote uniform crimping and expansion of the frame.

FIG. 19 shows one specific approach for securing the commissure portions122 of the leaflet structure 14 to the commissure window frame portions30 of the frame. In this approach, the flexible connector 124 (FIG. 18)securing two adjacent sides of two leaflets is folded widthwise and theupper tab portions 112 are folded downwardly against the flexibleconnector. Each upper tab portion 112 is creased lengthwise (vertically)to assume an L-shape having an inner portion 142 folded against theinner surface of the leaflet and an outer portion 144 folded against theconnector 124. The outer portion 144 can then be sutured to theconnector 124 along a suture line 146. Next, the commissure tab assemblyis inserted through the commissure window 20 of a corresponding windowframe portion 30, and the folds outside of the window frame portion 30can be sutured to portions 144.

FIG. 19 also shows that the folded down upper tab portions 112 can forma double layer of leaflet material at the commissures. The innerportions 142 of the upper tab portions 112 are positioned flat againstlayers of the two leaflets 41 forming the commissures, such that eachcommissure comprises four layers of leaflet material just inside of thewindow frames 30. This four-layered portion of the commissures can bemore resistant to bending, or articulating, than the portion of theleaflets 41 just radially inward from the relatively more-rigidfour-layered portion. This causes the leaflets 41 to articulateprimarily at inner edges 143 of the folded-down inner portions 142 inresponse to blood flowing through the prosthetic valve during operationwithin the body, as opposed to articulating about or proximal to theaxial struts of the window frames 30. Because the leaflets articulate ata location spaced radially inwardly from the window frames 30, theleaflets can avoid contact with and damage from the frame. However,under high forces, the four layered portion of the commissures can splayapart about a longitudinal axis adjacent to the window frame 30, witheach inner portion 142 folding out against the respective outer portion144. For example, this can occur when the prosthetic valve 10 iscompressed and mounted onto a delivery shaft, allowing for a smallercrimped diameter. The four-layered portion of the commissures can alsosplay apart about the longitudinal axis when the balloon catheter isinflated during expansion of the prosthetic valve, which can relievesome of the pressure on the commissures caused by the balloon, reducingpotential damage to the commissures during expansion.

After all three commissure tab assemblies are secured to respectivewindow frame portions 30, the lower edges of the leaflets 41 between thecommissure tab assemblies can be sutured to the inner skirt 16. Forexample, as shown in FIG. 20, each leaflet 41 can be sutured to theinner skirt 16 along suture line 154 using, for example, Ethibond Excel®PET thread. The sutures can be in-and-out sutures extending through eachleaflet 41, the inner skirt 16, and each reinforcing strip 72. Eachleaflet 41 and respective reinforcing strip 72 can be sewn separately tothe inner skirt 16. In this manner, the lower edges of the leaflets aresecured to the frame 12 via the inner skirt 16. As shown in FIG. 20, theleaflets can be further secured to the skirt with blanket sutures 156that extend through each reinforcing strip 72, leaflet 41 and the innerskirt 16 while looping around the edges of the reinforcing strips 72 andleaflets 41. The blanket sutures 156 can be formed from PTFE suturematerial. FIG. 21 shows a side view of the frame 12, leaflet structure14 and the inner skirt 16 after securing the leaflet structure 14 andthe inner skirt 16 to the frame 12 and the leaflet structure 14 to theinner skirt 16.

FIG. 22 shows a flattened view of the outer skirt 18 prior to itsattachment to the frame 12. The outer skirt 18 can be laser cut orotherwise formed from a strong, durable material such as PET or variousother suitable synthetic or natural materials configured to restrictand/or prevent blood-flow therethrough. The outer skirt 18 can comprisea substantially straight lower edge 160 and an upper edge portion 162defining a plurality of alternating projections 164 and notches 166, orcastellations. The outer skirt 18 can also comprise a plurality ofopenings 167 (e.g., 12 in the illustrated embodiment) disposed on anintermediate portion 169 (i.e., the portion between the lower edge 160and the upper edge portion 162) of the outer skirt 18. The openings 167are spaced from the lower edge 160 and the upper edge portion 162 suchthat the material of the outer skirt 18 separates the openings 167 fromthe lower edge 160 and the upper edge portion 162.

As best shown in FIG. 3, in some embodiments, a lower edge portion 174of the outer skirt 18 can be wrapped around the inflow end 15 of theframe 12, and the lower edge 160 of the outer skirt 18 can be attachedto the lower edge 84 of the inner skirt 16 and/or the frame 12 at theinflow end of the prosthetic valve 10. In some embodiments, the outerskirt 18 can be attached to the inner skirt 16, for example, withsutures or a suitable adhesive.

In lieu of or in addition to sutures, the outer skirt 18 can be attachedto the inner skirt 16, for example, by ultrasonic welding. Ultrasonicwelding can provide several significant advantages. For example,ultrasonic welding can be relatively less time consuming and lessexpensive compared to suturing, while also providing improved strength.

As shown in FIG. 1, each projection 164 of the outer skirt 18 can beattached to the third row III of struts 26 (FIG. 5) of the frame 12. Theprojections 164 can, for example, be wrapped over respective struts 26of row III and secured with sutures 168.

As can be seen in FIGS. 1-3, the outer skirt 18 is secured to the frame12 such that when the frame is in its expanded configuration (e.g., whendeployed in a subject), there is excess material between the lower edge160 and the upper edge portion 162 that does not lie flat against theouter surface of the frame 12. The outer skirt 18 can be secureddirectly to frame 12 and/or indirectly to frame 12, for example, bysecuring the outer skirt 18 to the inner skirt 16, which is directlysecured to the frame 12. In the expanded configuration of the prostheticvalve, the distance between the upper and lower attachment points of theouter skirt 18 decreases (foreshortens), resulting in radial expansionof the outer skirt 18. Additionally, the excess material between thelower and upper edges of the outer skirt 18 allows the frame 12 toelongate axially when crimped without any resistance from the outerskirt 18.

The outer skirt 18 can comprise an axial length or height Hs. In someembodiments, Hs is the height of the outer skirt 18, less the lower edgeportion 174 that is wrapped around the inflow end 15 of the frame 12, asbest shown in FIGS. 1, 3, and 22. In some embodiments, the height H_(s)can be substantially the same as the axial length between the upperattachment point of the outer skirt 18 to the frame 12 and the inflowend 15 of the frame 12 when the frame 12 is fully crimped. In suchembodiments, when the frame 12 is fully crimped, the outer skirt 18 canlie flat against the outer surface of the frame 12. In otherembodiments, the height H_(s) of the outer skirt 18 can exceed the axiallength between the upper attachment point of the outer skirt 18 to theframe 12 and the inflow end 15 of the frame 12 when the frame 12 isfully crimped. In such embodiments, the outer skirt 18 can comprise aplurality of creases 170 (e.g., twelve in the illustrated embodiment).

As best shown in FIG. 3, the creases 170 can extend axially from thelower edge 160 toward the intermediate portion 169 of the outer skirt18. The creases 170 can be aligned circumferentially with respectiveprojections 164, and the outer skirt 18 can be oriented with respect tothe frame 12 such that the creases 170 are circumferentially alignedbetween a respective pair of apices 22 a (FIG. 5) that are formed by thestruts 22 at the inflow end 15 of the frame 12. For example, the creases170 can be circumferentially aligned along a respective vertical line172 (FIGS. 2 and 5) that is parallel to the longitudinal axis of theframe 12 and bisects the frame 12 at a location equidistant from eachapex 22 a of a respective pair of apices 22 a. In this manner, thecreases 170 can cause excess material of the outer skirt 18 to retractradially inwardly between the apices 22 a and into the inflow end 15 ofthe frame 12 when the prosthetic valve 10 is crimped from the expandedconfiguration. As best shown in FIG. 2, each crease 170 can becircumferentially aligned with a respective opening 167 and projection164 along a respective line 172.

Referring to FIGS. 27-28, in lieu of or in addition to the creases 170(FIG.1), the outer skirt 18 can be attached and/or positioned relativeto the frame 12 such that the lower edge 160 of the outer skirt 18contacts the inflow end 15 of the frame 12 at locations (e.g., apices 22a) that are offset relative to locations (e.g., the junctions 64) atwhich the upper edge portion 162 of the outer skirt 18 contacts theoutflow end 19 of the frame 12. Configuring the outer skirt 18 and theframe 12 in this manner can cause excess material of the outer skirt 18to retract inwardly between the apices 22 a of the frame 12 when theprosthetic valve 10 is crimped from the expanded configuration (e.g.,FIG. 27) to the collapsed configuration (e.g., FIG. 28), as shown inFIG. 28.

This configuration also spreads the deformed fabric of the collapsedouter skirt 18 over a relatively large distance, which reduces theamount of outer skirt material per cross sectional area and flattens theouter skirt 18 around the crimped frame 12, thus reducing the crimpedprofile of the prosthetic heart valve 10. Reducing the crimped profileof the prosthetic heart valve 10 can reduce the push force necessary tomove the prosthetic heart valve 10 relative to a patient's vasculatureor a delivery cylinder of a delivery apparatus. It can also reduce thecompression force that is exerted upon the leaflets 41 to achieve aparticular crimp profile, which can reduce and/or eliminate damage tothe leaflets 41 caused by over compressing the leaflets 41 duringcrimping and/or delivery of the prosthetic heart valve 10 to animplantation location.

Retracting the excess material within the frame 12 below the leaflets 41when the prosthetic valve 10 is crimped advantageously allows theprosthetic valve 10 to have a relatively large outer skirt 18, which cansignificantly reduce perivalvular leakage, while minimizing the radialcrimp profile of the prosthetic valve 10. For example, the height H_(s)of the outer skirt 18 can be about 9 mm to about 25 mm or about 13 mm toabout 20 mm, with about 19 mm being a specific example. The height H_(f)of the frame 12 in the radially expanded state can be about 12 mm toabout 27 mm or about 15 mm to about 23 mm, with about 20 mm being aspecific example. The outer skirt 18 can be sized such that a ratioH_(s):H_(f), where H_(s) (FIG. 22) is the height of the outer skirt 18,and H_(f) (FIG. 5) is the height of the frame 12 in the expanded state,can be between about 0.75 to about 0.95. In some embodiments, the ratioH_(s):H_(f) can be between about 0.80 to about 0.90 or about 0.84 toabout 0.87. In one particular embodiment, the ratio H_(s):H_(f) can be0.86.

Providing a relatively larger outer skirt 18 allows the prosthetic valve10 to be positioned in a wider range of positions relative to the nativeannulus, while providing adequate perivalvular sealing. This improvedrange can make the prosthetic valve 10 easier to position during theimplantation procedure. It also allows the prosthetic valve to adapt togreater variation in native annulus anatomy.

In addition, the creases 170 can assist the outer skirt 18 in collapsingin a predetermined, uniform manner when the prosthetic valve is crimpedand allows the outer skirt 18 to expand to its functional state morequickly and consistently when deploying the prosthetic valve 10, asfurther described below.

Each crease 170 can be formed, for example, by overlapping adjacentportions of the outer skirt 18 and securing them together. The creasescan then be secured in the overlapped state, for example, by sutures,ultrasonic welding, and/or an adhesive. The creases 170 can be referredto as permanent creases in that the creases are retained when theprosthetic valve 10 is in a radially compressed state and a radiallyexpanded state.

As best shown in FIG. 22, the openings 167 can be laterally(circumferentially in FIGS. 1-3) spaced apart relative to adjacentopenings 167 and be laterally (circumferentially in FIGS. 1-3) alignedwith a respective projection 164. The openings 167 can also becircumferentially aligned with respective creases 170, as best shown inFIGS. 1 and 3. For example, the projections 164, the openings 167, andthe creases 170 can be aligned along the respective vertical lines 172,as best shown in FIG. 2. Aligning the openings 167 and the creases 170can, for example, allow blood to quickly enter, and thus expose muchmore surface area of the skirt material to blood. In addition, theoverlapped portions of the outer skirt 18 can expand when the prostheticvalve is initially deployed, as further described below.

The openings 167 can comprise various shapes. For example, the openings167 can comprise a tear-drop shape, as shown in the illustratedembodiment. In other embodiments, the openings can be circular,elliptical, rectangular, etc.

The prosthetic valve 10 can be configured for and mounted on a suitabledelivery apparatus for implantation in a subject. Several catheter-baseddelivery apparatuses are known; a non-limiting example of a suitablecatheter-based delivery apparatus includes that disclosed in U.S. PatentApplication Publication No. 2013/0030519, which is incorporated byreference herein in its entirety, and U.S. Patent ApplicationPublication No. 2012/0123529.

To implant a plastically-expandable prosthetic valve 10 within apatient, the prosthetic valve 10 including the outer skirt 18 can becrimped on an elongated shaft 180 of a delivery apparatus, as best shownin FIG. 14. The prosthetic valve, together with the delivery apparatus,can form a delivery assembly for implanting the prosthetic valve 10 in apatient's body. The shaft 180 comprises an inflatable balloon 182 forexpanding the prosthetic valve within the body. With the balloon 182deflated, the prosthetic valve 10 can then be percutaneously deliveredto a desired implantation location (e.g., a native aortic valve region).Once the prosthetic valve 10 is delivered to the implantation site(e.g., the native aortic valve) inside the body, the prosthetic valve 10can be radially expanded to its functional state by inflating theballoon 182.

Alternatively, a self-expanding prosthetic valve 10 can be crimped to aradially collapsed configuration and restrained in the collapsedconfiguration by inserting the prosthetic valve 10, including the outerskirt 18, into a sheath or equivalent mechanism of a delivery catheter.The prosthetic valve 10 can then be percutaneously delivered to adesired implantation location. Once inside the body, the prostheticvalve 10 can be advanced from the delivery sheath, which allows theprosthetic valve to expand to its functional state.

FIG. 23 shows an exemplary embodiment of an outer skirt 200. The outerskirt 200 can comprise a first end portion 202 (i.e., the upper endportion as depicted in FIG. 23), a second end portion 204 (i.e., thelower end portion as depicted in FIG. 23), and an intermediate portion206 disposed between the first and second end portions 202, 204.

The first end portion 202 of the outer skirt 200 can include a pluralityof alternating projections 208 and notches 210 and can also include aplurality of first openings 212. The first end portion 202 can beconfigured similar to the projections 164, the notches 166, and theopenings 167 of the outer skirt 18. For example, the first openings 212can be circumferentially aligned with the projections 208 andcircumferentially offset relative to the notches 210. The first endportion 202 can be attached to an inner skirt and/or frame of aprosthetic heart valve, as further described below.

The first openings 212 can comprise various sizes and/or shapes. Forexample, as shown in FIG. 23, the first openings 212 comprise a“tear-drop” shape. In other embodiments, the first openings 212 can belarger (e.g., elongate) or smaller and can comprise various other shapes(e.g., circular, rectangular, or ovular) than those shown in theillustrated embodiment.

The first end portion 202 of the outer skirt 200 can comprise firstouter diameter. In some embodiments, the first, outer diameter of thefirst end portion 202 is at least substantially similar to a second,outer diameter of the second end portion 204 and smaller than a third,outer diameter of the intermediate portion 206. In other embodiments,the first diameter of the first end portion 202 can be smaller than thesecond diameter of the second end portion 204 and the third diameter ofthe intermediate portion 206. In yet other embodiments, the firstdiameter of the first end portion 202 can be larger than the seconddiameter of the second end portion 204 and can be smaller than the thirddiameter of the intermediate portion 206.

The second end portion 204 of the outer skirt 200 can comprise asubstantially straight lower edge 214. The second end portion 204 can beattached to an inner skirt and/or frame of a prosthetic heart valve, asfurther described below. The second diameter of the second end portioncan be smaller than the third diameter of the intermediate portion 206.

The intermediate portion 206 of the outer skirt 200 can comprise aradially outwardly facing surface 216. As shown, in some embodiments,the surface 216 can be relatively flat. In other embodiments, thesurface 216 can be relatively tapered, from the first end portion 202 tothe second end portion 204, or vice versa. In yet other embodiments, thesurface 216 can be relatively curved or rounded.

In some embodiments, the surface 216 of the intermediate portion 206 cancomprise a plurality of second openings 217. The second openings 217 canbe spaced apart relative to each other, circumferentially aligned withthe notches 210 of the first end portion 202, and circumferentiallyoffset relative to the first openings 212 and the projections 208 of thefirst end portion 202. The second openings 217 can comprise variousshapes and/or sizes, including diamond-shaped (as shown in FIG. 23),circular, rectangular, ovular, etc. In alternative embodiments, thesurface 216 can be formed without the second openings 217.

The intermediate portion 206 can also comprise first and secondtransition sections 218, 220 separated relative to each other by thesurface 216 and disposed adjacent to the first and second end portions202, 204, respectively. In some embodiments, the transition sections218, 220 can be at least substantially perpendicular to the surface 216.In such embodiments, the outer diameter of the outer skirt 200 abruptlytransitions from the respective first and second diameters of the firstand second end portions 202, 204 to the third diameter of theintermediate portion 206 in a step- or flange-like manner. In otherembodiments, the transition sections 218, 220 can be angled between therespective end portions 202, 204 and the surface 216 such that the outerdiameter of the outer skirt 200 tapers from the respective first andsecond diameters of the end portions 202, 204 to the third diameter ofthe intermediate portion 206.

The outer skirt 200 can be coupled to a frame and/or an inner skirt of aprosthetic heart valve similar to the manner in which the outer skirt 18is coupled to the frame 12 and/or the inner skirt 16 of the prostheticheart valve 10. For example, the outer skirt 200 can be attached to aframe and/or inner skirt of a prosthetic heart valve by sutures and/orultrasonic welding.

The outer skirt 200 can be formed of materials such as PET, PTFE, ePTFE,polyurethane, polyester, and/or other suitable materials configured torestrict and/or prevent blood-flow therethrough. In some embodiments,the outer skirt 200 can be formed from a generally flat strip (e.g.,similar to the outer skirt 18 as shown in FIG. 22) and formed into atube by welding the ends together, as shown in FIG. 23. In otherembodiments, the outer skirt 200 can be formed by weaving the outerskirt 200 into a tubular shape. The intermediate portion 206 can beformed, for example, by shape-setting the material to a desiredconfiguration (e.g., as shown in FIG. 23).

The outer skirt 200 can be configured to be radially compressed to adelivery configuration and to radially expand from the deliveryconfiguration to a function configuration, in a manner similar to theouter skirt 18. In some embodiments, the outer skirt 200 can beself-expandable, such as by including Nitinol threads in the outer skirt200.

In this manner, the outer skirt 200 in conjunction with the inner skirt16 can reduce and/or eliminate perivalvular leakage between a frame of aprosthetic heart valve and a native annulus. As a result, the outerskirt 200 can improve functionality of a prosthetic heart valve and thusimprove functionality of a patient's heart.

FIGS. 24-26 show an exemplary embodiment of an outer skirt 300. FIG. 24shows a flattened view of the outer skirt 300 prior to its attachment toa prosthetic heart valve. FIGS. 25-26 show the outer skirt 300 attachedto the prosthetic heart valve 10 in lieu of outer skirt 18.

Referring to FIG. 24, the outer skirt 300 can comprise a first endportion 302 (i.e., the upper end portion as depicted in FIG. 24), asecond end portion 304 (i.e., the lower end portion as depicted in FIG.25), and an intermediate portion 306 disposed between the first andsecond end portions 302, 304. The first end portion 302 of the outerskirt 300 can include a plurality of alternating projections 308 andnotches 310, or castellations. The second end portion 304 of the outerskirt 300 can comprise a substantially straight lower edge 312 and canhave a plurality of openings 314. The openings 314 can be laterallyspaced apart relative to each other and laterally aligned with theprojections 308 of the first end portion 302 and laterally offsetrelative to the notches 310 of the first end portion 302. The openings314 can comprise various sizes and/or geometric shapes, includingcircular, ovular, rectangular, and/or combinations of shapes.

Referring to FIG. 25, the projections 308 of the first end portion 302can be attached to the inner skirt 16 and/or the frame 12 of theprosthetic heart valve 10 using sutures (as shown) and/or ultrasonicwelding. As shown in FIG. 26, the lower edge 312 of the second endportion 304 can be attached to the inner skirt 16 and/or the frame 12 ofthe prosthetic heart valve 10 using sutures (as shown) and/or ultrasonicwelding.

The outer skirt 300 can be formed of materials such as PET, PTFE, ePTFE,polyurethane, polyester, and/or other suitable materials configured torestrict and/or prevent blood-flow therethrough.

The outer skirt 300 can reduce and/or eliminate perivalvular leakagewhen the prosthetic heart valve 10 is implanted in a native heart valveannulus (e.g., a native aortic valve annulus or a native mitral valveannulus). For example, blood flowing from the inflow end portion 15(FIG. 26) toward the outflow end portion 19 (FIG. 25) of the prostheticheart valve 10 (i.e., antegrade blood flow) can enter the outer skirt300 through the openings 314 of the second end portion 304, as bestshown FIG. 26. Similarly, blood flowing from the outflow end portion 19toward the inflow end portion 15 of the prosthetic heart valve 10 (i.e.,retrograde blood flow) can enter the outer skirt 300 through the notches310 of the first end portion 302, as best shown in FIG. 25. Theblood-flow entering the openings 314 and/or the notches 310 cannot passdirectly through the outer skirt 300 because the openings 314 and thenotches 310 are circumferentially offset relative to each other.

FIG. 29 shows an exemplary embodiment of an outer skirt 400. The outerskirt 400 can be configured similar to the outer skirt 18 of theprosthetic heart valve 10 and can be attached to the prosthetic heartvalve 10 in a manner similar to the outer skirt 18. In some embodimentsand in lieu of or in addition to creases at the inflow end portion 15 ofthe prosthetic heart valve 10 (e.g., the creases 170 of the outer skirt18), the outer skirt 400 can have creases 402 extending axially from afirst end portion 404 of the outer skirt 400 to a second end portion 406of the outer skirt 400. The creases 402 can be circumferentially alignedwith notches 408 and circumferentially offset relative to projections410 of the first end portion 404.

In this manner, the outer skirt 400 can expand from a compressedconfiguration to an expanded configuration (and vice versa) in a uniformand/or predictable manner, similar to a bellows or an accordion. As aresult, the creases 402 facilitate uniform crimping and/or expansionand/or reduce the crimped radial profile of a prosthetic heart valve incompressed delivery configuration.

In some embodiments, the outer skirt 400 can comprise one or more reedsor valves configured to allow blood to flow into and/or through theouter skirt 400.

The outer skirt 400 can be formed, for example, by shape setting theouter skirt in this manner. In some embodiments, the creases 402 can beformed by ultrasonic welding.

FIGS. 30-31 show cross-sectional views of the frame 12, the inner skirt16, and the outer skirt 18 in an alternative embodiment of theprosthetic heart valve 10 in its expanded configuration (e.g., whendeployed in a subject). FIG. 30 shows a cross-sectional view of theframe 12, the inner skirt 16, and the outer skirt 18 through verticalline 172 (FIGS. 2 and 5) and FIG. 31 shows a cross-sectional view of theframe 12, the inner skirt 16, and the outer skirt 18 through verticalline 173 (FIGS. 2 and 5).

Referring to FIGS. 30 and 31, the inner skirt 16 comprises an upper edgeportion 48 and a lower edge portion 50. The upper edge portion 48 of theinner skirt 16 can be secured to the inside of the frame 12. The upperedge portion 48 of the inner skirt 16 can be secured to the inside offrame 12 via sutures 70 as previously described and as best shown inFIG. 21. Alternatively, the upper edge portion 48 of the inner skirt 16can be secured to the inside of frame 12 via adhesive and/or ultrasonicwelding in addition to or in lieu of sutures 70. In the illustratedembodiment of FIGS. 30 and 31, the upper edge portion 48 of the innerskirt 16 is secured to struts 28 (not shown in FIGS. 30 and 31) viasutures 70 as best shown in FIG. 22. Alternatively, the upper edgeportion 48 of the inner skirt 16 can be secured to any other portion orportions of the frame 12. The upper edge portion 48 is shown looselyattached to the frame in FIGS. 30-31 for purposes of illustration, buttypically is tightly secured to the frame struts as depicted in FIG. 22.

In the illustrated embodiment of FIGS. 30 and 31, the lower edge portion50 of the inner skirt 16 is wrapped around the inflow end portion 15 ofthe frame 12 and is exposed to the outside of frame 12. Still referringto FIGS. 30 and 31, the upper edge portion 162 of the outer skirt 18 canbe secured to the outside of the frame 12 as previously described. Theupper edge portion 162 of the outer skirt 18 can contain projections 164as best shown in FIG. 22 that can be secured to struts 26 (not shown inFIGS. 30 and 31) with sutures 168 as best shown in FIG. 1, although suchprojections are not required and the upper edge can be straight.

The lower edge portion 174 of the outer skirt 18 can be folded inwardtowards the frame 12 such that folded lower edge portion 174 of theouter skirt 18 is adjacent to the wrapped lower edge portion 50 of theinner skirt 16. The folded lower edge portion 174 of the outer skirt 18and the wrapped lower edge portion 50 of the inner skirt 16 can besecured together and/or secured to the frame 12. In the illustratedembodiment of FIGS. 30 and 31, the folded lower edge portion 174 of theouter skirt 18 and the wrapped lower edge portion 50 of the inner skirt16 are secured only to the apices 22 a of the frame 12 via sutures 74,with each suture extending through the lower edge portion 50, the loweredge portion 174 and around a respective apex 22 a. These additionallayers of material at the inflow end of the valve increase the materialsurface area at the inflow end of the valve.

In the illustrated embodiment, the lower edge portion 50 of the innerskirt 16 is shown extending over the lowermost row I of struts 22 alongthe outer surface of the frame. In other embodiments, the lower edgeportion 50 can extend farther along the outer surface of the frame andcan cover additional rows of struts 22, including rows II, III, or IV.Similarly, the folded lower edge portion 174 of the outer skirt 18 isshown extending axially over the lowermost row I of struts 22, but canextend farther along the outer surface of the frame and can coveradditional rows of struts 22, including rows II, III, or IV.

In other embodiments, the folded lower edge portion 174 of the outerskirt 18 and the wrapped lower edge portion 50 of the inner skirt 16 canbe secured to any other portion of the frame 12. In other embodiments,the folded lower edge portion 174 of the outer skirt 18 and the wrappedlower edge portion 50 of the inner skirt 16 can be secured to each otherand/or to the frame 12 via adhesive or ultrasonic welding in addition toor in lieu of the sutures 74.

In the illustrated embodiment of FIGS. 30 and 31, the lower edge portion174 of the outer skirt 18 and the lower edge portion 50 of the innerskirt 16 are loosely secured together at the inflow end portion 15 ofthe frame 12 and these two layers are secured to the frame only at theapices 22 a. This loose connection between the skirt layers, along withthe discrete (spaced apart) connections to the frame apices, allowsantegrade blood to more easily flow into the space between the frame 12and the outer skirt 18, exposing more of the layers of skirt material toblood, which can enhance the sealing properties, thereby reducing oreliminating perivalvular leakage.

In alternative embodiments, the lower edge portion 174 of the outerskirt 18 and the lower edge portion 50 of the inner skirt 16 can betightly sutured or otherwise secured to each other along the entirecircumference of both skirts. Also, one or both layers of the skirts 16,18 can be tightly sutured to the frame 12 along the entire circumferenceof the frame 12 (e.g., to the lower rung of struts 22), rather than justto the apices 22 a.

FIGS. 32-34 show another embodiment of an outer skirt 500. FIG. 32 showsa flattened view of the outer skirt 500 prior to its attachment to theprosthetic heart valve 10. FIGS. 33-34 show the outer skirt 500 in afolded configuration as discussed further below.

Referring to FIG. 32, the outer skirt 500 can comprise a first endportion 502 (i.e., the upper end portion as depicted in FIG. 32), asecond end portion 504 (i.e., the lower end portion as depicted in FIG.32), and an intermediate portion 506 disposed between the first andsecond end portions 502, 504. The first end portion 502 of the outerskirt 500 can include a plurality of alternating projections 508 andnotches 510, or castellations. The second end portion 504 of the outerskirt 500 can comprise a plurality of overlapping portions 512 and canhave a plurality of openings 514 paired with the overlapping portions.Each pair of an opening 514 and an overlapping portion 512 can belaterally spaced apart relative to each other and laterally aligned withthe projections 508 of the first end portion 502 and laterally offsetrelative to the notches 510 of the first end portion 502. When placedaround the stent, each overlapping portions 512 is radially aligned witha corresponding opening 514. The openings 514 can comprise various sizesand/or geometric shapes, including circular, ovular, rectangular, and/orcombinations of shapes.

Referring to FIGS. 33 and 34, the overlapping portions 512 of the secondend portion 504 can be folded upwards such that each overlapping portion512 covers one of the openings 514. FIG. 33 shows a view of the outerskirt 500 where the overlapping portions 512 are folded behind theopenings 514, as viewed from the outside of the skirt 500. FIG. 34 showsa view of the outer skirt 500 similar to FIG. 33, but as viewed from theinside of the skirt 500. In some embodiments, the outer skirt 500 ofFIGS. 32-34 can be used in place of the outer skirt 18 in the exemplaryembodiment of FIGS. 30-31. In such an embodiment, the overlappingportions 512 are folded inwards towards the frame 12 and are secured tothe folded lower edge portion 50 of the inner skirt 16 with sutures 74.

The overlapping portions 512 can cover and seal the openings 514 fromthe inside of the outer skirt 500. In addition, the overlapping portions512 provide an additional layer of material between the frame 12 and therest of the outer skirt 500. These layers provide additional materialsurface area and the openings expose more of the material to blood, thusenhancing the sealing effect.

It should be noted that, in some embodiments, the outer skirts 200, 300,500 can comprise creases similar to the creases 170, 402 of the outerskirt 18. The creases can be configured to facilitate uniform crimpingand/or expansion and/or to reduce the crimped radial profile of aprosthetic heart valve in compressed delivery configuration. In someembodiments, the creases can be formed by ultrasonic welding.

FIGS. 35-37 and 40 show various implantation positions for a prostheticheart valve 10, including implantation within a dock or anchor placedinside the patient's body prior to valve implantation. FIG. 35 shows theprosthetic heart valve 10 implanted in the native aortic valve of apatient.

FIG. 36 shows the prosthetic heart valve 10 implanted in the pulmonaryartery of a patient for replacing or enhancing the function of adiseased pulmonary valve. Due to the variations in the size and shape ofthe native pulmonary valve and the pulmonary artery, the prostheticvalve 10 can be implanted within a radially expandable outer dockingdevice 600. The docking device 600 can comprise a radially expandableand compressible annular stent 602 and a sealing member 604 that coversall or a portion of the stent and can extend across the inner surfaceand/or outer surface of the stent. The docking device 600 is configuredto engage the inner wall of the pulmonary artery and can accommodatevariations in patient anatomy. The docking device 600 also cancompensate for the expanded prosthetic heart valve 10 being much smallerthan vessel in which it is placed. The docking device 600 also can beused to support a prosthetic valve in other areas of the patient'sanatomy, such as, the inferior vena cava, superior vena cava, or theaorta. Further details of the docking device 600 and methods forimplanting the docking device and a prosthetic valve are disclosed, forexample, in co-pending U.S. application Ser. No. 15/422,354, filed Feb.1, 2017, which is incorporated herein by reference.

FIG. 37 shows the prosthetic heart valve 10 implanted in the nativemitral valve of a patient using a docking device in the form of ahelical anchor 700. The helical anchor 700 can include one or more coils702 deployed in left atrium and one or more coils 704 deployed in theleft ventricle and radially outside of the native mitral valve leaflets706. When the prosthetic valve 10 is deployed within the native valve,the native leaflets are compressed or pinched between the prostheticvalve 10 and the anchor 700 to retain the prosthetic valve in place.Further details of the helical anchor 700 and methods for implanting theanchor and a prosthetic valve are disclosed, for example, in co-pendingU.S. Application No. 62/395,940, filed Sep. 16, 2016, which isincorporated herein by reference.

FIGS. 38 and 39 show a docking device 800 for a prosthetic heart valve,according to another embodiment. The docking device 800 can include aradially expandable and compressible frame 802 having an outer portion804, an inner portion 806 disposed coaxially within one end portion ofthe outer portion 804, and a curved transition portion 808 extendingbetween and connecting the inner portion 806 and the outer portion 804.The docking device 800 can further include a sealing member 810extending over the inner surface of the inner portion 806, a portion ofthe outer surface of the outer portion 804 adjacent the inner portion806, and the transition portion 808.

FIG. 40 shows the docking device 800 implanted in a vessel 820, whichcan be, for example, the inferior vena cava, superior vena cava, or theascending aorta. As shown, a prosthetic valve 10 can be deployed withinthe inner portion 806 of the docking device 800. Similar to the dockingdevice 600, the docking device 800 can compensate for the expandedprosthetic heart valve 10 being much smaller than vessel in which it isplaced. The docking device 800 is particularly suited for implanting aprosthetic valve in the inferior vena cava for replacing or enhancingthe function of the native tricuspid valve. Further details of thedocking device 800 and methods for implanting the docking device and aprosthetic valve are disclosed, for example, in co-pending U.S.application Ser. No. 16/034,794, filed Jul. 13, 2018, which isincorporated herein by reference.

General Considerations

It should be understood that the disclosed embodiments can be adapted todeliver and implant prosthetic devices in any of the native annuluses ofthe heart (e.g., the pulmonary, mitral, and tricuspid annuluses), andcan be used with any of various approaches (e.g., retrograde, antegrade,transseptal, transventricular, transatrial, etc.). The disclosedembodiments can also be used to implant prostheses in other lumens ofthe body. Further, in addition to prosthetic valves, the deliveryassembly embodiments described herein can be adapted to deliver andimplant various other prosthetic devices such as stents and/or otherprosthetic repair devices.

For purposes of this description, certain aspects, advantages, and novelfeatures of the embodiments of this disclosure are described herein. Thedisclosed methods, apparatus, and systems should not be construed asbeing limiting in any way. Instead, the present disclosure is directedtoward all novel and nonobvious features and aspects of the variousdisclosed embodiments, alone and in various combinations andsub-combinations with one another. The methods, apparatus, and systemsare not limited to any specific aspect or feature or combinationthereof, nor do the disclosed embodiments require that any one or morespecific advantages be present or problems be solved. For example, anouter skirt for a prosthetic heart valve can include one or morefeatures disclosed skirt 18, skirt 200, skirt 300, skirt 400, and/orskirt 500.

Although the operations of some of the disclosed embodiments aredescribed in a particular, sequential order for convenient presentation,it should be understood that this manner of description encompassesrearrangement, unless a particular ordering is required by specificlanguage set forth below. For example, operations described sequentiallymay in some cases be rearranged or performed concurrently. Moreover, forthe sake of simplicity, the attached figures may not show the variousways in which the disclosed methods can be used in conjunction withother methods. Additionally, the description sometimes uses terms like“provide” or “achieve” to describe the disclosed methods. These termsare high-level abstractions of the actual operations that are performed.The actual operations that correspond to these terms may vary dependingon the particular implementation and are readily discernible by one ofordinary skill in the art.

As used in this application and in the claims, the singular forms “a,”“an,” and “the” include the plural forms unless the context clearlydictates otherwise. Additionally, the term “includes” means “comprises.”Further, the terms “coupled” and “associated” generally meanelectrically, electromagnetically, and/or physically (e.g., mechanicallyor chemically) coupled or linked and does not exclude the presence ofintermediate elements between the coupled or associated items absentspecific contrary language.

As used herein, the term “proximal” refers to a position, direction, orportion of a device that is closer to the user and further away from theimplantation site. As used herein, the term “distal” refers to aposition, direction, or portion of a device that is further away fromthe user and closer to the implantation site. Thus, for example,proximal motion of a device is motion of the device toward the user,while distal motion of the device is motion of the device away from theuser. The terms “longitudinal” and “axial” refer to an axis extending inthe proximal and distal directions, unless otherwise expressly defined.

As used herein, the terms “integrally formed” and “unitary construction”refer to a construction that does not include any welds, fasteners, orother means for securing separately formed pieces of material to eachother.

As used herein, the term “coupled” generally means physically coupled orlinked and does not exclude the presence of intermediate elementsbetween the coupled items absent specific contrary language.

As used herein, operations that occur “simultaneously” or “concurrently”occur generally at the same time as one another, although delays in theoccurrence of one operation relative to the other due to, for example,spacing, play or backlash between components in a mechanical linkagesuch as threads, gears, etc., are expressly within the scope of theabove terms, absent specific contrary language.

In view of the many possible embodiments to which the principles of thedisclosed invention may be applied, it should be recognized that theillustrated embodiments are only preferred examples of the invention andshould not be taken as limiting the scope of the invention. Rather, thescope of the invention is defined by the following claims. We thereforeclaim as our invention all that comes within the scope and spirit ofthese claims.

We claim:
 1. An implantable prosthetic valve comprising: an annularframe comprising an inflow end and an outflow end and being radiallycollapsible and expandable between a radially collapsed configurationand a radially expanded configuration; a leaflet structure positionedwithin the frame and secured thereto; an annular inner skirt positionedaround an inner surface of the frame, wherein the inner skirt comprisesan outflow edge portion secured to the frame and an inflow edge portionsecured to the frame; and an outer skirt positioned around an outersurface of the frame, wherein the outer skirt comprises an outflow edgeportion secured to the frame and an inwardly folded inflow edge portionthat is secured to the inflow edge portion of the inner skirt.
 2. Theprosthetic valve of claim 1, wherein the inflow edge portion of theinner skirt wraps around the inflow end of the frame and extends atleast partially along an outer surface of the frame.
 3. The prostheticvalve of claim 1, wherein the inflow edge portion of the inner skirt issecured to the frame at discrete, spaced-apart locations.
 4. Theprosthetic valve of claim 3, wherein the inflow edge portion of theouter skirt is secured to the inflow edge portion of the inner skirtonly at locations on the inflow edge portion of the inner skirt that aresecured to the frame.
 5. The prosthetic valve of claim 2, wherein theframe further comprises a plurality of struts forming a plurality ofcircumferentially spaced apices at the inflow end of the frame, andwherein the inflow edge portion of the inner skirt is secured to theframe only at the apices.
 6. The prosthetic valve of claim 5, whereinthe inflow edge portion of the outer skirt is secured to the inflow edgeportion of the inner skirt only at locations on the inflow edge portionof the inner skirt that are secured to the apices of the frame.
 7. Theprosthetic valve of claim 1, wherein the inflow edge portion of theinner skirt is secured to the frame with discrete, spaced-apart sutures.8. The prosthetic valve of claim 1, wherein the outflow edge portion ofthe outer skirt comprises a plurality of alternating projections andnotches, and wherein the projections are secured to the frame and thenotches are not directly secured to the frame.
 9. The prosthetic valveof claim 1, wherein the outer skirt further comprises an intermediateportion between the inflow edge portion and the outflow edge portion andwherein the intermediate portion comprises a plurality of openings. 10.The prosthetic valve of claim 9, wherein the openings are aligned withthe proj ections.
 11. The prosthetic valve of claim 9, wherein theinflow edge portion of the outer skirt comprises a plurality ofoverlapping portions that are angularly aligned with the openings,wherein the overlapping portions are folded inwardly towards the outflowend of the frame, and wherein the overlapping portions are secured tothe inflow edge portion of the inner skirt.
 12. The prosthetic valve ofclaim 11, wherein the overlapping portions are secured to the inflowedge portion of the inner skirt only at locations on the inflow edgeportion of the inner skirt that are secured to the frame.
 13. Theprosthetic valve of claim 11, wherein the overlapping portions arefolded such that each of the overlapping portions is radially alignedwith a corresponding one of the openings when the overlapping portionsare secured to the inner skirt.
 14. The prosthetic valve of claim 1,wherein the outer skirt is secured to the inner skirt by sutures. 15.The prosthetic valve of claim 1, wherein the inner and outer skirts areconfigured such that when the prosthetic valve is implanted, antegradeblood can flow through a space between the inflow edge portion of theinner skirt and the inflow edge portion of the outer skirt.
 16. Theprosthetic valve of claim 1, wherein the inflow edge portion of theinner skirt is loosely stitched to the inflow edge portion of the outerskirt.
 17. An assembly for implanting a prosthetic heart valve,comprising: a delivery apparatus comprising an elongate shaft; and aprosthetic heart valve, comprising: an annular frame comprising aninflow end and an outflow end and being radially collapsible andexpandable between a radially collapsed configuration and a radiallyexpanded configuration; a leaflet structure positioned within the frameand secured thereto; an annular inner skirt positioned around an innersurface of the frame, wherein the inner skirt comprises an outflow edgeportion secured to the frame and an inflow edge portion that wrapsaround the inflow end of the frame and extends at least partially alongan outer surface of the frame, the inflow edge portion being secured tothe frame; and an outer skirt positioned around the outer surface of theframe, wherein the outer skirt comprises an outflow edge portion securedto the frame and an inwardly folded inflow edge portion that is securedto the inflow edge portion of the inner skirt, wherein the prostheticheart valve is coupled to the shaft of the delivery apparatus.
 18. Amethod of implanting a prosthetic heart valve, comprising: radiallycompressing the prosthetic heart valve to a radially compressedconfiguration; wherein the prosthetic valve comprises: an annular framecomprising an inflow end and an outflow end and being radiallycollapsible and expandable between a radially collapsed configurationand a radially expanded configuration; a leaflet structure positionedwithin the frame and secured thereto; an annular inner skirt positionedaround an inner surface of the frame, wherein the inner skirt comprisesan outflow edge portion secured to the frame and an inflow edge portionthat wraps around the inflow end of the frame and extends at leastpartially along an outer surface of the frame, the inflow edge portionbeing secured to the frame; and an outer skirt positioned around theouter surface of the frame, wherein the outer skirt comprises an outflowedge portion secured to the frame and an inwardly folded inflow edgeportion that is secured to the inflow edge portion of the inner skirt,coupling the prosthetic heart valve to the distal end portion of adelivery apparatus; inserting the distal end portion of the deliveryapparatus and the prosthetic heart valve into a patient's body;positioning the prosthetic heart valve adjacent a native valve of thepatient's heart; and radially expanding the prosthetic heart valve sothat it engages the native valve.
 19. The method of claim 18, whereinthe inflow edge portion of the inner skirt is secured to the frame atdiscrete, spaced-apart locations.
 20. The method of claim 19, whereinthe inflow edge portion of the outer skirt is secured to the inflow edgeportion of the inner skirt only at locations on the inflow edge portionof the inner skirt that are secured to the frame.